The state of the art in worm reduction gearing has long been almost unchanged. Worm reduction gears have been made with a standard box-like casing to which a cover is screwed on either side in which a bearing and a seal are placed and which extend in a base in which two bores are cut through for fastening the worm reduction gear. On its ends the worm reduction gear has covers screwed to the casing.
As they have been constructed heretofore, worm reduction gears are not suitable for manufacture on automatic machines and robots. As a result, they are excessively expensive and do not have widespread availability. They are not suitable for simultaneous bearing and driving of the same loads. Sealing and centering are imperfect and unreliable. The existing reduction gear types are complicated to assemble; the worm and the worm wheel are not always fixed within the tolerances required because the assembly depends more or less on a human factor--the engine-fitter, who has to hold the sides of the worm reducing gear casing in his hands while trying to adjust them with gaskets and bolts during his assembly of the unit.
Conventional worm reduction gears do not allow optional installation, suspension, carrying, and driving of the same loads, and do not allow optional location and adaptation to just any user. For the same loads, the existing worm reduction gears are much larger and heavier than they have to be. In addition, in case of known, well established worm reduction gears a great variety of gears are to be made, varying in volume, weight, and power.